University of Texas at Austin
Ser and Estar One More Explanation
This site explains the tricky grammatical option of the two "to be" verbs, ser and estar. The following situations are discussed: joining two nouns, adjective phrases, and prepositional phrases.
Trent University
Mas Arriba: Condiciones (Estar)
This resource provides an interactive Spanish exercise on the verb ESTAR and conditions. The activity consists of full-color drawings, audio clips, instant feedback and vocabulary help.
Other
Practice and Review Ser vs. Estar
An excellent review of the uses of ser and estar. Provides useful examples. After reviewing, the user can take a practice quiz to ensure complete understanding.